private void Que(string q = "")
        {
            string constring = en.connectstr();
            SqlConnection conn = new SqlConnection(constring);
            SqlCommand cmd = new SqlCommand();
            cmd.CommandType = CommandType.Text;
            cmd.CommandText = q;
            cmd.Connection = conn;
            try
            {
                conn.Open();
            }
            catch (SqlException) { en.message(); }
            cmd.ExecuteNonQuery();
            conn.Close();
            this.Hide();
            add a = new add();
            a.Show();

        }